Apparatus and method for making information carrying cards through radiation curing, and resulting products

ABSTRACT

The disclosure provides a method for forming an information carrying card or a core layer of an information carrying card using a radiation curing, and an apparatus configured to provide such a radiation curing. The method includes providing a carrier layer that defines at least one cavity, providing an inlay layer supporting at least one electronic component, and positioning at least a portion of the inlay layer in the at least one cavity. The method further comprises dispensing a radiation crosslinkable polymer composition over the inlay layer, and irradiating the radiation crosslinkable polymer composition.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 14/913,039, filed Feb. 19, 2016, which is a national phase entryunder 35 U.S.C. § 371 of International Patent Application No.PCT/US2014/050987, filed Aug. 14, 2014, which claims priority to U.S.Provisional Patent Application No. 61/868,304, filed Aug. 21, 2013, andU.S. Provisional Patent Application No. 61/904,138, filed Nov. 14, 2013,the entireties of which are herein incorporated by reference.

FIELD OF THE INVENTION

The disclosure relates to information carrying cards such as smartcards. More particularly, the disclosed subject matter relates to anapparatus and a method for making an information carrying card or itscore layer using radiation curing, and the resulting informationcarrying cards.

BACKGROUND OF THE INVENTION

Information carrying cards provide identification, authentication, datastorage and application processing. Such cards or parts include keycards, identification cards, telephone cards, credit cards, bankcards,tags, bar code strips, other smart cards and the like. Counterfeitingand information fraud associated with traditional plastic cards causestens of billions of dollars in the losses each year. As a response,information carrying cards are getting “smarter” to enhance security.Smart card technologies provide solutions to prevent fraud and decreaseresulting losses.

Information carrying cards often include an integrated circuit (IC)embedded in a thermoplastic material, such as polyvinyl chloride (PVC).Information has been input and stored in the integrated circuit before atransaction. In use, information carrying cards work in either a“contact” or “contactless” mode. In contact mode, an electroniccomponent on the card is caused to directly contact a card reader orother information receiving device to establish an electromagneticcoupling. In contactless mode, the electromagnetic coupling between thecard and the card reading device is established through electromagneticaction at a distance, without the need for physical contact. The processof inputting information into the IC of the information carrying cardalso works in either of these two modes.

When information carrying cards become “smarter,” the amount ofinformation stored in each card often increases, and the complexity ofthe embedded IC's also increases. The cards also need to withstandflexing to protect sensitive electronic components from damage as wellas offer good durability during use. A relatively easy and full-scalecommercial process having improved productivity at low cost is alsodesired.

SUMMARY OF THE INVENTION

The invention provides an apparatus and a method for making a core layerfor an information carrying card or an information carrying card, usingradiation curing. The disclosure also provides the resulting core layerfor an information carrying card, and the information carrying card.

In some embodiments, a method for forming an information carrying cardor a core layer of an information carrying card is provided. The methodcomprises the following steps: providing a carrier layer that defines atleast one cavity, providing an inlay layer supporting at least oneelectronic component, and positioning at least a portion of the inlaylayer in the at least one cavity. The method further comprisesdispensing a radiation crosslinkable polymer composition over the inlaylayer, and irradiating the radiation crosslinkable polymer compositionto form a crosslinked polymer composition.

In some embodiments, the carrier layer is a first thermoplastic layercomprising at least one thermoplastic material. The radiationcrosslinkable polymer composition, which may be a liquid or a paste,comprises a curable precursor selected from the group consisting ofacrylate, methacrylate, urethane acrylate, silicone acrylate, epoxyacrylate, methacrylate, silicone, urethane and epoxy.

In some embodiments, the method comprises a step of applying vacuum tothe radiation crosslinkable polymer composition. The method may furthercomprise disposing a second thermoplastic layer above the carrier layerafter the step of applying the radiation crosslinkable polymercomposition over the inlay layer. In some embodiments, the methodcomprises a step of providing a release film above the carrier layerafter applying the radiation crosslinkable polymer composition over theinlay layer.

In the step of irradiating (i.e. curing) the radiation crosslinkablepolymer composition, the carrier layer, the inlay and the radiationcrosslinkable composition are pressed under a pressure. Such a curing isperformed through radiation emitted toward at least one side of thecarrier layer, for example, two sides of the carrier layer. The pressuremay be in the range of from 0.01 MPa to 3 MPa in some embodiments.

The radiation comprises at least one of visible light, ultraviolet (UV),infrared (IR), electronic beam (EB), and combinations thereof. In someembodiments, the curing step is performed at room temperature. In someembodiments, additional heat, for example, moderate heat may be used inthe step of curing the radiation crosslinkable polymer composition.

In some embodiments, the crosslinked polymer composition provides aprintable surface. The method can comprise a step of directly printingwords or images onto a surface of the crosslinked polymer composition. Aportion of the crosslinked polymer composition may be disposed over atop surface of the carrier layer, for example, covering the top surfaceof the carrier layer.

The disclosure also provides a method for fabricating an informationcarrying card, comprising forming a core layer as described. The methodfor fabricating an information carrying card further compriseslaminating at least one thermoplastic film on each side of the corelayer of the information carrying card, or bonding at least onethermoplastic film on each side of the core layer of the informationcarrying card. The methods provided in this disclosure are useful inmaking a heat-sensitive information carrying card. The inlayer layercomprises at least one electronic component being heat sensitive.

The present disclosure also provides an apparatus used for carrying outthe methods described. The apparatus comprises at least one supportlayer having both a plurality of ribs and a plurality of channelsbetween two adjacent ribs, a plurality of radiation sources and aradiation transparent layer. Each of the plurality of radiation sourcesis disposed in one respective channel and configured to provideradiation. A radiation transparent layer is coupled with the at leastone support layer and configured to protect the plurality of radiationsources. The radiation comprises at least one of visible light,ultraviolet (UV), infrared (IR), electronic beam (EB) and combinationsthereof. In some embodiments, each of the plurality of radiation sourcescomprises light emitting diode (LED) configured to emit UV light. Theplurality of radiation sources may be connected with a power source.

In the apparatus, the at least one support layer may be made of a metalsuch as aluminum, aluminum alloy, stainless steel, or any other suitablemetals or a combination thereof. The radiation transparent layer maycomprise glass, UV transparent ceramic, or transparent polymers such aspoly(methyl methacrylate) and polycarbonate. The at least one supportlayer may be coupled with the radiation transparent layer with a pliablelayer therebetween. The pliable layer may comprise a fluoropolymer, forexample, polytetrafluoroethylene (PTFE).

The disclosure also provides a system used for carrying out the methodsdescribed. The system comprises a bottom portion of an apparatus and atop portion of the apparatus. Each of the bottom portion and the topportion comprises at least one support layer having both a plurality ofribs and a plurality of channels between two adjacent ribs, a pluralityof radiation sources and a radiation transparent layer. Each of theplurality of radiation sources is disposed in one respective channel andconfigured to provide radiation. A radiation transparent layer iscoupled with the at least one support layer and configured to protectthe plurality of radiation sources. In some embodiments, the radiationtransparent layer in the bottom portion and the radiation transparentlayer in the top portion face to each other, and are configured to curea layered structure having a radiation crosslinkable polymer compositiondisposed therebetween. The radiation may comprise at least one ofvisible light, UV, IR, EB, and combinations thereof. For example, eachof the plurality of radiation sources may comprise LED configured toemit UV light.

The system may comprise a power source connected to the plurality ofradiation sources. The power source may supply a direct current (DC)directly to the plurality of radiation sources, or may comprise atransformer converting an alternating current (AC) to a direct current.The at least one support layer may be made of a metal such as aluminum,aluminum alloy, stainless steel, or any other suitable metal or acombination thereof. The radiation transparent layer may comprise glass,UV transparent ceramic or transparent polymers such as poly(methylmethacrylate) and polycarbonate. The at least one support layer may becoupled with the radiation transparent layer with a pliable layer, forexample, a fluoropolymer layer therebetween.

In some embodiments, the system further comprises a spacer disposedbetween the radiation transparent layer in the bottom portion and theradiation transparent layer in the top portion. The spacer has athickness to accommodate a layered structure. The layered structure maybe an information carrying card or a core layer of an informationcarrying card being fabricated. The spacer is configured to provide apredetermined final thickness of the information carrying card or thecore layer.

In some embodiments, the system also comprises a pressure unitconfigured to press the layered structure under a pressure whileirradiating the radiation crosslinkable polymer composition. Thepressure may be in the range of from 0.01 MPa to 3 MPa.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is best understood from the following detaileddescription when read in conjunction with the accompanying drawings. Itis emphasized that, according to common practice, the various featuresof the drawings are not necessarily to scale. In some instances, thedimensions of the various features are arbitrarily expanded or reducedfor clarity. Like numerals denote like features throughout thespecification and the figures.

FIGS. 1-6 illustrate cross sectional views of layered structures atdifferent steps in an exemplary process of forming a core layer of aninformation carrying card, in accordance with some embodiments.

FIG. 1 illustrates a sectional view of a first thermoplastic layerhaving at least one cavity optionally disposed over a release film.

FIG. 2 is a cross sectional view of the structure after an inlay layeris disposed partially or fully inside the cavity of the firstthermoplastic layer of FIG. 1.

FIG. 3 is a cross sectional view of the structure of FIG. 2 after acrosslinkable polymer composition is dispensed over the inlay layerinside the cavity.

FIG. 4 is a cross sectional view of the resulting structure after arelease film is placed over the structure of FIG. 3.

FIG. 5 illustrates the structure of FIG. 4 subject to UV radiation fromboth sides in accordance with some embodiments.

FIG. 6 is a cross sectional view of an exemplary core layer of aninformation carry card, which is fabricated according to the structurein FIGS. 1-6 and steps in FIG. 7.

FIG. 7 is a flow chart diagram illustrating an exemplary process offorming a core layer of an information carrying card or an informationcarrying card comprising a step of radiation curing, in accordance withsome embodiments.

FIG. 8 illustrates an exemplary inlay layer for an information carryingcard in some embodiments.

FIG. 9 is a cross sectional view of an exemplary frame having ribs andchannels for an apparatus configured to provide radiation in someembodiments.

FIG. 10 is a top down view of the frame of FIG. 9.

FIG. 11 is a cross sectional view of the fame of FIG. 9 having aplurality of radiation sources disposed in the channels.

FIG. 12 is a top down view of the frame of FIG. 11.

FIG. 13 is a cross sectional view of a bottom portion of the apparatusconfigured to provide radiation in accordance with some embodiments.

FIG. 14 is a top down view of the bottom portion of the apparatus shownin FIG. 13.

FIG. 15 is a cross sectional view of a top portion of the apparatusconfigured to provide radiation in accordance with some embodiments.

FIG. 16 is a top down view of a top (or upper) portion of the apparatushaving a certain orientation of the channels for the radiation sourcesin some embodiments.

FIG. 17 illustrates an exemplary apparatus used in a method for making acore layer of an information carrying card or the information carryingcard in accordance with some embodiments. The exemplary apparatuscomprises the bottom portion of FIG. 13 and the top portion of FIG. 15.

FIG. 18 illustrates the exemplary apparatus of FIG. 17 undercompression.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

This description of the exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. In the description, relativeterms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,”“below,” “up,” “down,” “top” and “bottom” as well as derivative thereof(e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should beconstrued to refer to the orientation as then described or as shown inthe drawing under discussion. These relative terms are for convenienceof description and do not require that any apparatus to be constructedor operated in a particular orientation. Terms concerning attachments,coupling and the like, such as “connected” and “interconnected,” referto a relationship wherein structures are secured or attached to oneanother either directly or indirectly through intervening structures, aswell as both movable or rigid attachments or relationships, unlessexpressly described otherwise.

For brevity, unless expressly stated otherwise, references to“information carrying card” or “smart card” made throughout thisdescription are intended to encompass at least key cards, identificationcards, telephone cards, credit cards, bankcard, power cards, tags, barcode strips, any part comprising an integrated circuit (IC), and thelike. “Information carrying card” or “smart card” also includes a widevariety of shapes, which include but are not limited to rectangularsheets, circular sheets, strips, rods and rings. “Information carryingcard” or “smart card” also includes any information carrying parts ofboth “contact” and “contactless” modes. “Information carrying card” or“smart card” also encompasses any information carrying cards with orwithout an on-board power supply. An information carrying cardcomprising a power supply is also referred as a “power card.”

In FIGS. 1-6 and 9-18, like items are indicated by like referencenumerals, and for brevity, descriptions of the structure, provided abovewith reference to the previous figures, are not repeated. The methodsdescribed in FIG. 7 are described with reference to the exemplarystructure described in FIGS. 1-6 and the apparatus and system describedin FIGS. 9-19.

1. Method for Making Information Carrying Card:

Some embodiments provide a method for forming an information carryingcard or a core layer of an information carrying card. The method maycomprise the following steps including: providing a carrier layer thatdefining at least one cavity, providing an inlay layer supporting atleast one electronic component, and positioning at least a portion ofthe inlay layer in the at least one cavity. The method further comprisesdispensing a radiation crosslinkable polymer composition over the inlaylayer, and irradiating (i.e. curing) the radiation crosslinkable polymercomposition using radiation such as visible lights, UV, IR, EB or acombination thereof, to form a crosslinked polymer composition.

The carrier layer may be a first thermoplastic layer comprising at leastone thermoplastic material. The radiation crosslinkable polymercomposition comprises a curable precursor selected from the groupconsisting of acrylate, methacrylate, urethane acrylate, siliconeacrylate, epoxy acrylate, methacrylate, silicone, urethane, epoxy or thelike. The radiation crosslinkable polymer composition may be a liquid ora paste, and can be degassed after dispensed over the inlay layer.

In some embodiments, a second thermoplastic layer, or a release film, orboth can be disposed above the carrier layer after the radiationcrosslinkable polymer composition is disposed over the inlay layer. Inthe curing step, the carrier layer, the inlay layer and the radiationcrosslinkable composition may be pressed under a pressure. The radiationmay be at least one of visible light, UV, IR, EB, and combinationsthereof.

In some embodiments, the crosslinked polymer composition provides aprintable surface. The method can comprise a step of directly printingwords or images onto a surface of the crosslinked polymer composition. Aportion of the crosslinked polymer composition may be disposed over atop surface of the carrier layer, for example, covering the top surfaceof the carrier layer.

The method can be used to make an information carrying card or its corelayer, which may be heat sensitive. The inlay layer comprises at leastone heat sensitive electronic component. The method can also be used tomake an information carrying card having high density of electroniccomponents. One example is a biometric information carrying card.Another example is an information carrying card having an inlay layerhaving at least one electronic component configured to display a onetime passcode (OTP). The inlay layer comprises at least one LCDcomponent in some embodiments. The inlay layer can also comprise EInkdisplay components, electrochromic components, electrophoreticcomponents or organic light emitting diodes (OLED), or any othersuitable electronic components, or a combination thereof.

The at least one electronic component can be partially or fully disposedinside the cavity over the carrier layer, depending on the relativesizes of the inlay layer and the cavity. The inlay layer may alsocomprise at least one sheet of metal, ceramic, metal containingmaterial, ceramic containing material, plastics or the like.

A general method for making a core layer for an information carryingcard and the resulting information carrying card in the presentdisclosure are disclosed in U.S. patent application Ser. No. 13/801,630filed Mar. 13, 2013, and U.S. patent application Ser. No. 13/801,677;filed Mar. 13, 2013, which are hereby incorporated by reference inentirety.

At step 41 of FIG. 7, a carrier layer 6 (e.g., a first thermoplasticlayer) is provided. The carrier layer 6 has at least one cavity.

Referring to FIG. 1, a carrier layer 6 that defines at least one cavity7 (or an opening) is disposed over a release film 2. The release film 2is optional in some embodiments. In some embodiments, no release film 2is used. Examples of release film 2 included but are not limited to asheet of polytetrafluoroethylene under the trade name Teflon®, any otherfluoropolymers, silicones, fluoropolymer or silicone coated films. Insome embodiment, release film 2 can include two release films, forexample, a second release film is disposed over a first release film.The two release films can be formed from the same material. In someembodiments, at least one breathable release film is used. Examples of abreathable release film is a silicone coated paper (e.g., a siliconecoated, unbleached parchment baking paper, available from Regency Wrapscompany under the trade name of “If you care”). Another example ofrelease film 2 is a parchment paper (27-81T or 35-81T) available fromPaterson Papers Company, Paterson, N.J.

Carrier layer 6 can be molded or laminated from one or more layers ofthermoplastic films. Examples of materials that are suitable for use informing carrier layer 6 include polyvinyl chloride (PVC), a copolymer ofvinyl chloride, polyolefin, polycarbonate, polyester, polyamide,acrylonitrile butadiene styrene copolymer (ABS), and the like. Carrierlayer 6 may be a PVC, or a copolymer of vinyl chloride and anothermonomer such as vinyl ether, vinyl ester or vinyl acetate, or a compoundor blend of PVC and a vinyl chloride polymer. Examples of PVC filmssuitable for use with the invention are available from suppliers such asKlockner Pentaplast of America, Inc. of Gordonsville, Va.; andShijiazhuang Eurochem Co. Ltd of China. Examples of such copolymerresins are available from Dow Chemical Company under trade name ofUCAR®, and from BASF of Ludwigshafen, Germany under trade name ofLaroflex®. UCAR® is a copolymer of vinyl chloride and vinyl acetate. Thegrades include YYNS-3, VYHH and VYHD. Laroflex® is a copolymer of vinylchloride and vinyl isobutyl ether. The grades include MP25, MP 35, MP45and MP60. All of these polymer resins may be supplied as fine powder. Apowder of these copolymers can be added to modify PVC resins for films.Carrier layer 6 having at least one cavity 7 can be formed bydie-cutting one or more thermoplastic film and then laminating andheating one or more thermoplastic films. For example, one thermoplasticfilm, which can be in the range of 0.025 mm to 0.5 mm in thickness, iscut with a hole and placed above another thermoplastic film, which canbe in the range of 0.025 mm to 0.25 mm in thickness. The two films arethen laminated to form a first thermoplastic layer 6 having at least onecavity 7.

At step 42 of FIG. 7, an inlayer layer 8 supporting at least oneelectronic component 10 is provided. At step 43, at least a portion ofinlayer layer 8 is disposed into the at least one cavity 7 of carrierlayer 6.

Referring to FIG. 2, at least one portion of inlay layer 8 is disposedinside at least one cavity 7 of carrier layer 6. Inlay layer 8 ispartially or fully disposed inside cavity 7. Inlay layer 8 can be fixedonto the surface of carrier layer 6 through heat bonding, adhesivebonding, or any other suitable method. In some embodiments, inlay layer8 or a surface of carrier layer 6 may be tacky without need of fixinginlay layer 8 onto the surface of carrier layer 6. Inlay layer 8comprises at least one active or passive electronic component 10embedded or surface mounted on a supporting film 12. Inlay layer 8 maycomprise a printed circuit board (PCB). Electronic components 10 may beembedded or surface mounted on the PCB supporting material. Examples ofsupporting film 12 include but are not limited to polyimide, polyestersuch as PET, glass filled epoxy sheet such as FR-4. A printed circuitboard (PCB) having all the components are abbreviated as PCBa. Forbrevity, the references to PCB in this disclosure will be understood toencompass any PCBs including PCBa. Examples of electronic components 10inside inlay layer 8 include but are not limited to active or passiveelectronic components, e.g., an integrated circuit (IC), a battery for a“power card,” an antenna, and a functional component such as lightemitting diodes (LED). In some embodiments, electronic components 10 areconfigured to display a one time passcode (OTP). Electronic components10 are interconnected via wires or traces 14. Supporting film 12 may bea polymer based dielectric material. In some embodiments, inlay layer 8may comprises components such as a battery fixed onto a small piece of apolymer film such as a PVC film, and then inlay layer 8 comprising thecomponents and the polymer film may be disposed into the cavity in thefirst thermoplastic layer 6.

Inlay layer 8 may have any dimension relative to the size of a cavity inthe first thermoplastic layer 6. Inlay layer 8 may be partially or fullydisposed in such a cavity. In some embodiments, the size of the cavityon first thermoplastic layer 6 is larger than the size of inlay layer 8.Inlay layer 8 may be fully disposed in the cavity. In some embodiments,the size of the cavity in first thermoplastic layer 6 is substantiallythe same as or slightly larger than the size of inlay layer 6 of PCB.The shape of the cavity often matches with the shape of inlay layer 8.In some embodiments, the size of the at least one cavity on firstthermoplastic layer 6 is less than the size of inlay layer 8. The sizeof the at least one cavity is substantially the same as or slightlylarger than a portion of inlay layer 8 of the PCB. For example, theshape and size of one cavity may match with one electronic component 10.Examples of electronic components 10 include but are not limited to abattery, an antenna, or an active or passive electronic component, e.g.,an integrated circuit (IC) in inlay layer 8. In some embodiments, inlaylayer 8 may comprise a piece or a sheet of metal, ceramic, metalcontaining material, ceramic containing material, plastic or the like.Examples of suitable materials for this piece or sheet include but arenot limited to platinum, copper, tungsten, metallized power containingmaterials, alumina, silica, and ceramic powder containing materials.This piece or sheet may be in a certain color or weight, having certainvisual or other sensational characteristics.

In some embodiments, inlay layer 8 comprises electronic components 10,which are configured to provide an information carrying card, which maybe heat sensitive, pressure sensitive, or both. A heat sensitivecomponent may withstand a maximum temperature below 150° C., forexample, in the range of 70-120° C. Examples of heat-sensitiveelectronic components 10 include but are not limited to LCD components,EInk display components, electrochromic components, electrophoreticcomponents, organic light emitting diodes (OLED), or any other suitableelectronic components, or a combination thereof. Examples of heatsensitive information carrying card include but are not limited to LCD,electrophoretic display, electronic ink display, electrochromic display,biometric information cards. One example is a biometric informationcarrying card. Another example is an information carrying card having aninlay layer having at least one electronic component configured todisplay a one time passcode (OTP).

FIG. 8 illustrates an exemplary inlay layer 30 for a biometricinformation carrying card. Inlay layer 30 comprises printed circuitboard (PCB). Inlay layer 30 may comprise a contact pad 32, a biometricsensor or sensor pad 33, a sealing bezel 34 for biometric sensor 33, padtraces 36 for electronic components, connecting traces 37, connectors 38connecting biometric sensor to PCB, and connector traces 39 forbiometric sensor 33. In some embodiments, some portions such as contactpad 32 and biometric sensor 33 may be cut open and exposed. Thebiometric information carrying card may be a smart card with contactmode. Connecting traces 37 may be used to contact a power supplied by abiometric reader for card activation.

At step 44 of FIG. 7, a radiation crosslinkable polymer composition 16is dispensed over inlay layer 8.

Referring to FIG. 3, a radiation crosslinkable polymer composition 16,is dispensed over carrier layer 6, and inlay layer 8 inside cavity 7.The radiation crosslinkable polymer composition 16 may be also dispensedover carrier layer 6 outside cavity 7 some embodiments. Composition 16may comprise a curable precursor, in a liquid or paste form. Such acurable precursor may be acrylate, methacrylate, urethane acrylate,silicone acrylate, epoxy acrylate, urethane, epoxy, silicone or thelike.

The curable precursor in the radiation crosslinkable polymer composition16 may comprise a monomer, an oligomer or pre-polymer having functionalgroups. The precursor is cross-linkable under a regular curingconditions including but not limited to radiation such as ultraviolet(UV) light, and radiation together with heat. The curable precursor maybe in liquid or paste form. Its viscosity may be in the range of1-100,000 cps. In some embodiments, the curable precursor is urethaneacrylate. These curable precursors are readily available from specialtychemical suppliers. Examples of these suppliers include but are notlimited to Dymax Corporation of Torrington, Conn. and Sartomer USA, LLCof Exton, Pa.

The radiation crosslinkable polymer composition 16 may be unfilled insome embodiments, and comprises filler or other additives in some otherembodiments. The crosslinkable polymer composition may comprise in therange of about 0.5 wt. % to about 80 wt. % of the filler. The filler canbe inorganic or organic filler. For example, the filler can be aparticulate thermoplastic filler such as polyolefin, polyvinyl chloride(PVC), a copolymer of vinyl chloride and at least another monomer, or apolyester such as polyethylene terephthalate (PET). The at least anothermonomer in the vinyl chloride co-polymer filler may be vinyl ester,vinyl acetate or vinyl ether in some embodiments. The particulatethermoplastic filler may be a compound or a blend comprising athermoplastic resin, for example, a compound or a blend comprising PVCor a modified PVC. Examples of such a copolymer are available from DowChemical Company under trade name of UCAR™, and from BASF ofLudwigshafen, Germany under trade name of Laroflex™. UCAR™ is acopolymer of vinyl chloride and vinyl acetate. The grades includeYYNS-3, VYHH and VYHD. Laroflex™ is a copolymer of vinyl chloride andvinyl isobutyl ether. The grades include MP25, MP 35, MP45 and MP60. Allof these polymer resins are often supplied in the form of fine powder.Particulate thermoplastic filler might be obtained through suspension oremulsion polymerization of one or more corresponding monomers or,through pulverization of solid plastics. The particulate form can be ofany size, by way of example and not limitation. The particles may be inthe range of 0.5-200 microns. In some embodiments, the particles are inthe range of 1-1000 nm.

Radiation cross-linkable polymer composition 16 may further comprise atleast one curative based on general principles of polymer chemistry.Such a radiation cross-linkable polymer composition 16 becomes a solidcross-linked composition 18 after curing. Preferably, such across-linked composition 18 is more flexible than carrier layer 6 insome embodiments. For example, the cross-linkable composition 16comprises a first curative for radiation curing and optionally a secondcurative for radiation curing. During the curing or cross-linkingreaction, such a cross-linkable composition transforms into a solidcross-linked polymer composition. Such a cross-linked polymercomposition 18 is also known in the art as a “thermosetting” polymer or“thermoset” to distinguish it from a thermoplastic polymer.

Examples of a suitable crosslinkable polymer composition 16 include butare not limited to a formulation comprising a curable precursor such asacrylate or urethane acrylate. Examples of such a formulation includebut are not limited to X-685-31-1 and X-685-31-2, available from DymaxCorporation of Torrington, Conn. X-685-31-1 is a formulation comprisingisobornyl acrylate, 2-hydroxyethyl methacrylate,2-hydroxy-3-phenoxypropyl acrylate, t-butyl perbenzoate and aphotoinitiator. Its viscosity is 1047 cP. X-685-31-2 is also aformulation comprising isobornyl acrylate, 2-hydroxyethyl methacrylate,2-hydroxy-3-phenoxypropyl acrylate, t-butyl perbenzoate and aphotoinitiator. Its viscosity is 1025 cP. These examples are onlyintended to illustrate embodiments in accordance with the invention, andas such should not be construed as imposing limitations upon the claims.

A radiation cross-linkable polymer composition 16 may be packed in asyringe and dispensed using the standard dispensing apparatus orequipment for adhesives, encapsulants, sealants and potting compounds.The amount of cross-linkable composition 16 to be dispensed can becalculated and controlled based on the volume of the cavity and inlaylayer 8.

At step 45 of FIG. 7, a release film 2 (or 2′) or a second thermoplasticlayer can be placed above carrier layer 6. Referring to FIG. 4, arelease film 2 as described is placed over the structure of FIG. 3. Therelease film 2 may be any kind of release films, and may be the same asthe release film 2 under carrier 6. Examples of the release film overthe structure of FIG. 3 include but are not limited to a breathablesilicone coated paper, a sheet of a fluoropolymer such as PTFE. Releasefilm 2 may be transparent, translucent, or opaque but transparent ortranslucent to UV or other radiation. In some embodiments, release film2 may include two release films. In some embodiments, release film 2 isa parchment paper (27-81T or 35-81T) available from Paterson PapersCompany, Paterson, N.J. It is surprisingly found that a translucent filmsuch as parchment paper (27-81T or 35-81T) can disperse radiations suchas UV to result in uniform curing of the cross-linkable composition 16.In some embodiments, no release film 2 is used.

Instead of release film 2, a second thermoplastic layer (not shown) isplaced above carrier layer 6. In some embodiments, a secondthermoplastic layer and release film 2 may be placed above carrier layer6. The second thermoplastic layer comprises a thermoplastic materialselected from polyvinyl chloride, copolymer of vinyl chloride,polyolefin, polycarbonate, polyester, polyamide, and ABS copolymer. Thesecond thermoplastic layer might be the same as the first thermoplasticlayer (carrier layer) 6. Its thickness may be in the range of 0.025 mmto 0.25 mm. This thermoplastic layer becomes a part of the core layer ifused. The second thermoplastic layer may be transparent, translucent, oropaque but transparent or translucent to UV or other radiation.

The radiation crosslinkable polymer composition 16 may be degassed in avacuum chamber after being dispensed over carrier layer 6, or after step45. A vacuum may be applied onto the crosslinkable polymer composition16 in a vacuum chamber. The pressure range is in the range of 10 Pa to1000 Pa. The vacuum can be maintained for 0.5 to 10 minutes, preferably1-3 minutes. The vacuum is released in the end of a cycle. One ormultiple cycles can be used to achieve a bubble free sample. Such avacuum process is performed at low temperature, preferably at roomtemperature.

At step 46 of FIG. 7, the radiation cross-linkable polymer composition16 is cured using radiation such as UV, IR, visible light, e-beam (EB),or a combination thereof.

Referring to FIGS. 4 and 5, the sandwiched structure of FIG. 4 is placedunder pressure, and irradiated with radiation in an apparatus asdescribed in FIGS. 17 and 18. As illustrated in FIG. 18, a spacer 68 canbe used to control the final thickness of the crosslinkable polymercomposition 16 over carrier layer 6, and thus the overall thickness ofthe core layer of an information carrying card or an informationcarrying card. Such a curing is performed through one type of radiationemitted toward at least one side of the carrier layer (i.e. one side ortwo sides of the carrier layer). The pressure may be in the range offrom 0.01 MPa to 3 MPa.

The one type of radiation may be at least one of visible light, UV, IR,EB, and combinations thereof. For example, UV may be used. In someembodiments, UV having a wavelength in the range of 350-400 nm is used.The curing time may be in the range from 10 seconds to 60 seconds. Insome embodiments, the curing may be performed at room temperature or ata temperature of 35-40° C. In some other embodiments, additional heat,for example, moderate heat at a temperature below 80° C., for example,in the range of from 50° C. to 80° C., may be used in the curing step.

Referring to FIG. 6, a core layer for an information carrying card isformed, after release film 2 (if used) is peeled off. The crosslinkablepolymer composition 16 becomes into the crosslinked polymer composition18 in solid state. Different reference numerals are used for the purposeof differentiation only even though they may share the same chemicalcomposition. Referring to FIG. 6, an exemplary core layer 22 of aninformation carry card comprises a first thermoplastic layer (carrierlayer) 6, an inlay layer 8, and a cross-linked polymer composition 18.Inlay layer 8 comprises electronic components 10, for example, at leastone printed circuit board (PCB), supporting film 12 and interconnects14. The electronic components 10, such as a battery and an active orpassive electronic components 10, are connected with interconnects 14.Electronic components 10 are embedded on supporting film 12. Thecross-linked polymer composition 18 fills the voids and remaining spacesinside the cavity on carrier layer 6 and inlay layer 8. In someembodiments, the cross-linked polymer composition 18 directly contactsthe outer surface of electronic components 10. Inlay layer 8 may haveany dimension relative to the size of a cavity in carrier layer 6. Inlaylayer 8 may be partially or fully disposed into such a cavity.

In some embodiments, a core layer of an information carry card caninclude a full open cavity for an inlay. The size of a cavity on thefirst thermoplastic layer 6 is larger than the size of inlay layer 8. Insome embodiments, such a cavity is close to but slightly smaller thanthe size of an information carrying card. Inlay layer 8 is fullydisposed into the cavity. The shape of the cavity may not be the same asthe shape of inlay layer 8. In some embodiments, an open inlay cavity isclose to the size of an inlay layer 8. The size of a cavity on the firstthermoplastic layer 6 is substantially the same as or slightly largerthan the size of inlay layer 8. The shape of the cavity matches with theshape of inlay layer 8. In this configuration, inlay layer 8 can befully disposed inside the cavity on carrier layer 6. In someembodiments, an exemplary core layer of an information carry cardincludes a window cavity partially for an inlay. The size of the atleast one cavity on carrier layer 6 is less than the size of inlay layer8. The size of the at least one cavity is substantially the same as orslightly larger than a portion of inlay layer 8. A portion of inlaylayer can be cut open for form one or more holes so that an electroniccomponent 10 can be fit into one of the holes. Electronic component 10in inlay layer 8 can be also inserted from one side of carrier layer 6.During the fabrication process, a crosslinkable composition 16 for thecrosslinked polymer composition 18 can be applied to from the other sideof the first thermoplastic layer 6.

A portion of the crosslinked polymer composition 18 may be disposed overa top surface of carrier layer 6, for example, covering the top surfaceof carrier layer 6. The thickness of the portion of the cross-linkedpolymer composition 18 above the top surface of carrier layer 6 can bein any thickness, for example, in the range of 1 micron to 100 micron inthickness.

The crosslinked polymer composition 18 may provide a printable surface.At step 47, words or images can be directly printed onto a surface ofthe crosslinked polymer composition 18.

Some embodiments provide a method for fabricating an informationcarrying card, comprising forming a core layer as described. The methodfor fabricating an information carrying card further compriseslaminating, or bonding at least one thermoplastic film on each side ofthe core layer of the information carrying card, as shown in step 48 ofFIG. 7. Hot lamination or adhesive bonding may be used. In a process ofadhesive bonding, any suitable adhesive may be used.

Examples of the at least one thermoplastic film includes but are notlimited to a printable thermoplastic film, a transparent film andcombinations thereof. Such a film may be made of PVC, PET or any othersuitable polymer films. In some embodiments, a printable film is animaging receiving layer, and may not be transparent and may containwhite pigments. In some other embodiments, words or images can bedirectly printed onto the crosslinked polymer composition 18 and anadditional printable film may not be used. Before the printing process,surface treatment may not be needed in some embodiments. Surfacetreatment may also be used to improve adhesion between two layers inother embodiments. Examples of surface treatment methods include but arenot limited to plasma treatment or corona treatment.

In some embodiments, a technique called “reversed printing technique”may be used. One side of a transparent film may be printed with a thinlayer of white pigments which may comprise printed words or images. Theprinted surface is bonded or laminated with the core layer as describedabove. The other side of the transparent film can be a shiny surface asthe top surface of an information carrying card.

The described methods are useful in making a heat-sensitive informationcarrying card. The inlayer layer comprises at least one electroniccomponent being heat sensitive. The information carrying card may havedifferent sizes. In some embodiments, the information carrying card mayhave a size following ISO/IEC 7810 standard. For example, an ID-1 typesmart card, which is for most of the banking card and ID cards, has asize of 85.6×53.98 mm.

The examples above are described using one information carrying card fordemonstration only. In a production process of making a core layer or aninformation carrying card, a sheet of core layer can comprise aplurality of units for a plurality of information carrying card. Duringor after the fabrication, the sheet can be cut into a plurality of corelayers or a plurality of information carrying cards.

2. Apparatus and System for Making Information Carrying Card or its CoreLayer

Referring to FIGS. 17 and 18, some embodiments provide an apparatus or asystem used for carrying out the methods described. FIGS. 9-18illustrate the method of making such an apparatus or system.

Referring to FIGS. 9 and 10, at least one support layer 52 having both aplurality of ribs 51 and a plurality of channels 53 between two adjacentribs is provided. Support layer 52 may be made of a metal such asaluminum, aluminum alloy, stainless steel, or any other suitable metalor a combination thereof. Ribs 51 are elongated ridges. Channels 53 areshallow trenches machined away from one side of support layer 52, asshown in FIG. 9. As shown in FIG. 10, ribs 51 and channels 53 may beparallel to each other.

Referring to FIGS. 11 and 12, a plurality of radiation sources 54 aredisposed in one respective channel 53 and configured to provideradiation such as UV, IR, visible light, EB, any other radiation orcombinations thereof. The plurality of radiation sources 54 may beconnected in parallel or in series through wires 56, and then connectedwith a power source (not shown) through wires 58. The power source maysupply a direct current (DC) directly to the plurality of radiationsources, or may comprise a transformer converting an alternating current(AC) to a direct current. Any suitable alternative arrangements may beused to connect and power radiation sources 54. In some embodiments,each of the plurality of radiation sources 54 comprises LED configuredto emit UV light. The UV light may have a specific wavelength orwavelength range (e.g., 450-400 nm). The wavelength may be tailored tomatch with the curing chemistry of the radiation crosslinkable polymercomposition 16. During a curing process using UV, radiation sources 54may not give off heat. Radiation sources 54 may be configured to provideIR, which optionally provide moderate heat.

Referring to FIGS. 13 and 14, a radiation transparent layer 64 and aspacer 68 are provided. The radiation transparent layer 64 may compriseglass, plastics or UV transparent ceramic such as aluminium oxynitrideunder tradename ALON® available from Surmet Corportion, Burlington,Mass. Transparent polymers such as poly(methyl methacrylate) andpolycarbonate can be also used. Poly(methyl methacrylate) is well knownunder the tradename PLEXIGLASS. Polycarbonate is available under thetradename LEXAN® from SABIC. A radiation transparent layer 64 may have asmooth finished surface. A radiation transparent layer 64 is coupledwith the at least one support layer 52 and configured to protect theplurality of radiation sources 54. The at least one support layer 52 maybe coupled with the radiation transparent layer 64 with a pliable layer62 therebetween. The pliable layer 62 may comprise a fluoropolymer, forexample, polytetrafluoroethylene.

The structure illustrated in FIG. 13 can be a bottom portion of anapparatus. Spacer 68 may be disposed over radiation transparent layer64. Spacer 68 may be a removable tape or film bonded on the periphery ofradiation transparent layer 64, and has a thickness to accommodate alayered structure such as a core layer or an information carrying cardto be fabricated as described in FIG. 18.

Referring to FIG. 15, similar to the bottom portion in FIGS. 13 and 14,a top portion of an apparatus can be provided for a system of thepresent disclosure. The bottom portion also comprises at least onesupport layer 52 having both a plurality of ribs 51 and a plurality ofchannels 53 between two adjacent ribs, a plurality of radiation sources54 and a radiation transparent layer 64. Each of the plurality ofradiation sources 54 is disposed in one respective channel 53 andconfigured to provide radiation. A radiation transparent layer 64 iscoupled with the at least one support layer 52 and configured to protectthe plurality of radiation sources 54 and provide a smooth surface. Theradiation may comprise at least one of visible light, UV, IR, EB, andcombinations thereof. For example, each of the plurality of radiationsources 54 may comprise light emitting diode (LED) configured to emitultraviolet (UV) light. As shown in FIG. 16, ribs 51 and channels 53 maybe parallel to each other, and may be in an orientation the same as ordifferent from that in the bottom portion of FIG. 14.

Referring to FIG. 17, the bottom portion of FIGS. 13 and 14 and the topportion of FIGS. 16 and 17 can be assembled to form an apparatus 70 in asystem 72. The radiation transparent layers 64 in each portion may faceto each other and are configured to cure a layered structure 20 having aradiation crosslinkable polymer composition 16 disposed therebetween.

Referring to FIG. 18, system 72 may comprise a pressure unit having twopressing plates 74 configured to press the layered structure 20 under apressure while curing the radiation crosslinkable polymer composition 16using a type of radiation. The pressure may be in the range of from 0.01MPa to 3 MPa. In some embodiments, the top or bottom portion ofapparatus 70 is fixed onto a respective pressing plate 74. System 72 maycomprise a power source connected to the plurality of radiation sources54. As described, system 72 may comprise a spacer 68 disposed betweenthe radiation transparent layer 64 in the bottom portion and theradiation transparent layer 64 in the top portion face. Spacer 68 may bea film, a sheet or a tape bonded onto a radiation transparent layer 64either in the top portion or the bottom portion of apparatus 70. Spacer68 has a thickness to accommodate a layered structure 20. Layeredstructure 20 is an information carrying card or a core layer of aninformation carrying card being fabricated as described. Spacer 68 isconfigured to provide a predetermined final thickness of the informationcarrying card or a core layer of an information carrying card. In system72, radiation transparent layer 64 having a smooth surface can provide asmooth surface of a resulting core layer or an information carryingcard.

In a fabrication process, system 72 including apparatus 70 is assembledwith a layered structure 20. Steps 41-46 of method 40 in FIG. 7 can beperformed accordingly. Layered structure 20 can be pressed under apressure and irradiated for a period of time (e.g., in the range of from10 seconds to 60 seconds). The radiation sources 54 can be turned offand the pressure can be released. After the layered structure 20 isremoved, another cycle of the process can be performed. In someembodiments, the fabrication process is in a batch process. In someembodiments, the fabrication process can be a continuous automatedproduction.

A critical requirement in the manufacture of a core layer for aninformation carrying card is to achieve a very smooth coplanar surfaceon the top and bottom so that the overlay sheets are applied andlaminated there is little to no visible deformation of the card graphicsand of final products. Thermal expansion and shrinkage occur to theconventional encapsulating materials used in other processes, resultingin warping of a core layer, and rough or deformed coplanar surface.

The methods described in the present disclosure provided a minimalshrinkage and yield a very smooth and coplanar surface, withwell-tailored and controlled thickness. The methods also offeradvantages including but are not limited to an increase in productionrate, a low temperature and low pressure (LTLP) process especially forheat sensitive components, and flexibility in product design andfabrication.

Although the subject matter has been described in terms of exemplaryembodiments, it is not limited thereto. Rather, the appended claimsshould be construed broadly, to include other variants and embodiments,which may be made by those skilled in the art.

What is claimed is:
 1. An apparatus comprising a top portion and abottom portion, each of the bottom portion and the top portioncomprising: at least one support layer having both a plurality of ribsand a plurality of channels between two adjacent ribs; a plurality ofradiation sources, each of the plurality of radiation sources disposedin one respective channel and configured to provide radiation; and aradiation transparent layer coupled with the at least one support layerand configured to protect the plurality of radiation sources.
 2. Theapparatus of claim 1, wherein the radiation comprises at least one ofvisible light, ultraviolet (UV), infrared (IR) and electronic beam (EB).3. The apparatus of claim 1, wherein each of the plurality of radiationsources comprises light emitting diode (LED) configured to emitultraviolet (UV) light.
 4. The apparatus of claim 1, wherein theplurality of radiation sources are connected with a power source.
 5. Theapparatus of claim 1, wherein the at least one support layer is made ofaluminum, aluminum alloy, stainless steel, or any other suitable metalor a combination thereof.
 6. The apparatus of claim 1, wherein theradiation transparent layer comprises glass, UV transparent ceramic,poly(methyl methacrylate), or polycarbonate.
 7. The apparatus of claim1, wherein the at least one support layer is coupled with the radiationtransparent layer with a pliable layer therebetween.
 8. The apparatus ofclaim 7, wherein the pliable layer comprises a fluoropolymer.
 9. Theapparatus of claim 1, wherein the plurality of radiation sources areconnected in series with wires disposed the plurality of channels.
 10. Asystem comprising a bottom portion of an apparatus; and a top portion ofthe apparatus, wherein each of the bottom portion and the top portioncomprises at least one support layer having both a plurality of ribs anda plurality of channels between two adjacent ribs; a plurality ofradiation sources, each of the plurality of radiation sources disposedin one respective channel and configured to provide radiation; and aradiation transparent layer coupled with the at least one support layerand configured to protect the plurality of radiation sources, and theradiation transparent layer in the bottom portion and the radiationtransparent layer in the top portion face to each other and areconfigured to cure a layered structure having a radiation crosslinkablepolymer composition disposed therebetween.
 11. The system of claim 10,wherein the radiation comprises at least one of visible light,ultraviolet (UV), infrared (IR) and electronic beam (EB).
 12. The systemof claim 10, wherein each of the plurality of radiation sourcescomprises light emitting diode (LED) configured to emit ultraviolet (UV)light.
 13. The system of claim 10 further comprising a power sourceconnected to the plurality of radiation sources.
 14. The system of claim13, wherein the power source supplies a direct current (DC) directly tothe plurality of radiation sources, or comprises a transformerconverting an alternating current (AC) to a direct current.
 15. Thesystem of claim 10, wherein the at least one support layer is made ofaluminum, aluminum alloy, stainless steel, or any other suitable metalor a combination thereof.
 16. The system of claim 10, wherein theradiation transparent layer comprises glass, UV transparent ceramic,poly(methyl methacrylate), or polycarbonate.
 17. The system of claim 10,wherein the at least one support layer is coupled with the radiationtransparent layer with a pliable layer therebetween.
 18. The system ofclaim 10 further comprising a spacer disposed between the radiationtransparent layer in the bottom portion and the radiation transparentlayer in the top portion face, and the spacer has a thickness toaccommodate a layered structure.
 19. The system of claim 10 furthercomprising a pressure unit configured to press the layered structureunder a pressure while curing the radiation crosslinkable polymercomposition using a type of radiation.
 20. The system of claim 19,wherein the pressure unit is configured to apply the pressure in a rangeof from 0.01 MPa to 3 MPa.